LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2018 >> Acadia Denali, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 274 (Lighting System - DTC B3891 To DTC C0297 And Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> Dome Lamps Malfunction >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2017 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.

Dome Lamp Switch Malfunction

  1. Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, open and close drivers door, disconnect the harness connector at the S12 Dome Lamp Switch. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 1 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Ignition ON.
  4. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Door.
    • If Cancel 
    1. Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the signal circuit terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K9 Body Control Module.
    • If On 
    1. Ignition OFF, disconnect the X7 harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the signal circuit terminal 3 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K9 Body Control Module.
    • If Door 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 2 and ground.
  6. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Cancel.
    • If not Cancel 
    1. Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 2 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If Cancel 
  7. Install a 3 A fused jumper wire between the signal circuit terminal 3 and ground.
  8. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is On.
    • If not On 
    1. Ignition OFF, disconnect the X7 harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 3 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If On 
  9. Test or replace the S12 Dome Lamp Switch.

Dome/Courtesy Lamps Malfunction

    NOTE:

    Each lighting component may need to be disconnected to isolate a short to ground. Use the schematics to identify the following:

    • Lighting components the vehicle is equipped with
    • Each component's control and ground circuit terminals
    • Component locations on the lighting control circuit
  1. Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, open and close drivers door, disconnect the harness connector at the component with inoperative dome/courtesy lamp. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the appropriate ground circuit terminal listed below and ground.
    • E8D Door Courtesy Lamp - Driver terminal 2
    • E8P Door Courtesy Lamp - Passenger terminal 2
    • E8J Instrument Panel Courtesy Lamp - Left terminal 2
    • E8K Instrument Panel Courtesy Lamp - Right terminal 2
    • E37LF Dome/Reading Lamps - Left Front terminal 6
    • E37RF Dome/Reading Lamps - Right Front terminal 6
    • E37LR Dome/Reading Lamps - Left Rear terminal B (Sedan)
    • E37RR Dome/Reading Lamps - Right Rear terminal B (Sedan)
    • E37R Dome/Reading Lamps - Rear terminal 3 (Coupe)
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Connect a test lamp between the appropriate control circuit terminal listed below and ground, ignition ON.
    • E8D Door Courtesy Lamp - Driver terminal 1
    • E8P Door Courtesy Lamp - Passenger terminal 1
    • E8J Instrument Panel Courtesy Lamp - Left terminal 1
    • E8K Instrument Panel Courtesy Lamp - Right terminal 1
    • E37LF Dome/Reading Lamps - Left Front terminal 2
    • E37RF Dome/Reading Lamps - Right Front terminal 2
    • E37LR Dome/Reading Lamps - Left Rear terminal C (Sedan)
    • E37RR Dome/Reading Lamps - Right Rear terminal C (Sedan)
    • E37R Dome/Reading Lamps - Rear terminal 2 (Coupe)
  4. Verify the test lamp turns ON and OFF when commanding the Courtesy Lamps ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the X7 harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K9 Body Control Module.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the X7 harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit terminal and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K9 Body Control Module.
    • If the test lamp turns ON and OFF 
  5. Test or replace the dome/courtesy lamp.
scientia non olet · About LEMON Manuals